SAB Biotherapeutics (SAB BIO) has announced progress in its Phase 1 clinical trial of SAB-142, a novel immunotherapy for type 1 diabetes (T1D). The trial, designed to assess the safety, tolerability, pharmacokinetic, pharmacodynamic, and immunogenicity of SAB-142, has completed enrollment of healthy volunteers and is now enrolling patients with T1D. The company presented these updates at the European Association for the Study of Diabetes (EASD) 60th Annual Meeting in Madrid.
Alexandra Kropotova, MD, MBA, Executive Vice President and Chief Medical Officer of SAB BIO, presented on "Protecting pancreatic beta cells with multi-target immunotherapy: SAB-142." SAB-142 is a first-in-class human anti-thymocyte immunoglobulin (hIgG) being developed as a disease-modifying treatment to delay the onset and progression of T1D.
Key Findings from the Phase 1 Trial
The Phase 1 trial, which commenced in November 2023, is a randomized, double-blind, placebo-controlled, single-ascending dose, adaptive design study. It aims to generate data on the differentiated safety and immunogenicity of SAB-142 and establish a proof of biological activity (POBA).
Notably, the trial has completed dosing at the target dose of 2.5mg/kg with SAB-142, and no observation of serum sickness was reported. This is a significant advantage over rabbit anti-thymocyte globulin (ATG), which often induces serum sickness in patients.
SAB-142: A Human Alternative to Rabbit ATG
SAB-142 is designed as a human alternative to rabbit ATG. Rabbit ATG has shown clinical validation in T1D trials, demonstrating the ability to slow down disease progression in patients with new or recent onset of Stage 3 type 1 diabetes. SAB-142's mechanism of action is analogous to that of rabbit ATG, targeting multiple immune cells involved in destroying pancreatic beta cells.
While rabbit ATG has demonstrated the ability to modulate the body’s immune response to help slow beta cell destruction and preserve insulin production, its use is often limited by the development of serum sickness and anti-drug antibodies. SAB-142, being a fully human antibody, aims to allow safe, consistent re-dosing without the risk of major adverse immune reactions.
Next Steps for SAB-142
SAB is progressing to enroll patients with T1D to supplement the last cohort of the Phase 1 study. The company has also elected to add a T1D patient cohort to establish the safety, tolerability, pharmacokinetic, and immunogenicity profile of SAB-142 in patients with T1D prior to initiating an upcoming Phase 2 SAFEGUARD study in patients with new-onset T1D. Topline Phase 1 data is expected by the end of the year.
"We are pleased with the continued progress of SAB-142 and its emerging safety profile to date," said Dr. Kropotova. "Our trial results to date definitively demonstrate a lack of serum sickness for our SAB-142 compound, which is a key differentiation compared to rabbit anti-thymocyte globulin... We continue to gather SAB-142 data that supports our commitment to developing a disease modifying immunotherapy to change the lives of people impacted by type 1 diabetes."
